Devices that exhibit differential negative resistance (DNR), also often referred to as negative differential resistance or negative differential conductance, do not function in agreement with Ohm's law. Instead, an increase in absolute voltage produces a decrease in absolute current, at least over a portion of an applied voltage range.
A DNR device that it commonly used in integrated circuits, particularly logic circuitry, is the tunnel diode (or Esaki diode). The DNR effect is displayed in tunnel diodes as a current dip in the forward I-V characteristics. For a certain range of forward voltages the current through the diode actually falls, instead of increasing, making it useful in certain switching applications, for instance.
It has recently been discovered that a chalcogenide glass structure may be configured with an excess of metal ions, e.g., Ag ions, to exhibit DNR behavior. U.S. patent application Ser. No. 10/193,529 by the inventor describes such a DNR exhibiting device suitable for use as a tunnel diode. This related application is incorporated by reference herein in its entirety. The DNR behavior of the device is characterized by a very good peak-to-valley current ratio evident in its forward I-V curve. It would be advantageous if such DNR behavior could be utilized for a memory function.